Prepare for 2.7.2 final release.

Prepare for 2.7.2rc1 release.

Update version numbers. Add jffi-dll-droppings to .hgignore so as to avoid
complaints from the build after test.

Establish java environment in test_jython_initializer (fixes #2810)

This change addresses a test failure observed in test_jython_initializer
where the build Java is ahead of the default installed Java.
We "inherit" java.home in the otherwise-stripped environment.

--HG--
extra : amend_source : b595dda0ceda305384b4b9fb5cd2f9a84af79df1

Begin to identify as Jython 2.7.2b2.

As well as changing the version numbers in build scripts as we have
often before, this clarifies (in comments) a numbering policy change by
which developer and snapshot builds identify as the version we are
working *towards*, with a -DEV or -SNAPSHOT suffix, not the last one
released and a "+" suffix. This appears to be the common practice (in
the Maven eco-system).

Prepare for 2.7.2b1 release.

Update version reported to 2.7.2a1

Updating versions for 2.7.1 release.

Merge up.

Version wording change.

Prepare for 2.7.1rc1 release.